Improvement in insulating telegraphic conductors



D. BROOKS. Insulating Telegraphic-Conductors.

No. 210,986. Patented Dec. 17,1878.

NJETERS, PHOTO LTHOGRA DAVID BROOKS, 6F PHILADELPHIA,

PENNSYLVANIA, ASSIGNOR TO THE BROOKS UNDERGROUND TELEGRA?H CONSTRUCTION SOMPANY, (LIM- FEED) Sjrllllh lliAGE.

llVl'PPrGVEMENT lN INSULATING TELEGRAPHEC CUNDUGTQRSl Snecilieation formin iart of Letters Patent No. 210 986., dated December 17 1878 a i ilication filed .L a: 9 I 7 1 December 2, 1878.

To all whom it may concern:

it known that l, DAVID BROOKS, of Philadelphia, Pennsylvania, have invented a new and use il improvement in Insulating Tele graph-llires, of which the following is a specification:

lily invention relates to an improvement in the mode of insulating telegraph-wires tor which Letters Patent No. 165,535 were granted to me July 1-3, 1875, my present improvement consisting in keeping a clothed wire or wires 'l in pipes in a constantly-insulated i ion by maintaining within the said pipes, and under pressure, a supply of insulatingliquid, which is in dir ct contact with the said clothed. wire or wires, as explained hereinafter.

In carrying out my said patented invention, I iirstclothed a wire with cotton, hemp, jute, or other cheap absorbent material, and then insulated one or more of these clothed wires b saturating them with melted paratiine, I then placed the covered and insulated wire or cable of wires in a tube, and maintained within the latter a constant supply of parallineoil,

l have ascertained that this preliminary iusulation of the clothed wires with paratline is not essential to their complete insulation, and that, if the iibrcus material with which the wires are thed be entirely deprived of moisture and gases in. the first instance, ordinary petroleum and other liquids, after they are rendered nhydrous, may be used as insulat ing me ians, providing they are maintained in constant and intimate contact with the clothed wires,

The preliminary heat-in g or" the clothed wires or cable of wires may be eil'ected in different ways, may, ror instance, be subjected in an o n to about 300 to 520 Fahrenheit :to-r a su "*ient length of time to insure the vapor on of all the moisture contained in rous wrapping and the evolving of all e ierated by subjecting the fibers hen (preferably while it is hot) the gas to heat, steeping insulating-h on L he cable in heated petroleum or other in, Another wires or ca linseed oil, for instanceor other liquid which will not evaporate at a temperature of 350 for the bath should be maintained at about that temperature. After this has been done the cable may be boiled in water in which chlorine or bleaching-powder has been dissolved, so that all traces of acids or gases may be removed, its the clothing; of the wires is made somewhat tender by the above treatment, the cable may be wrapped with hemp, jute, or other cheap fibrous n52 The ca- .ble is then placed in a bath of any liquid insulating medium-connnon petroleum, for instance the said bath being maintained at a temperature of about 230 Fahrenheit, and this steeping is continued until insulation ceases to increase. The cable, being new deprived of all moisture and gases and thoroughly insulated, is pulled through a pipean ordinary lap or but-t welded iron tube, for instanee-in doing which the fibrous clothing of the wires is protected by the EL JOVG'llIGIltioned wrapping.

Before the cable is pulled into the pipe the interior of the latter is deprived of all moist ture. This may be done by heating the pipe or by introducin into it pulverized quichlimc, which absorbs the moisture.

The manner of connecting the pipes con taining the cables and maintaining the wrapping-s in a proper insulated condition after the pipes are laid will be best explained by reference to the accompanying drawing, in which- T G represent the ends of two adjoining pipes, both containing cables similar to that above describe: l) is a T-picce, to which the pipes are secured, and into a branch, 72 of this T-piece the ends of the wires of the cable in each pipe are turned up, after being deprived the wrapping, so that they may be twisted together, metal to metal, after which the twisted wires are again securely wrapped with fibrous material and the branch h closed by a suitable screw plug or cap. Before the latter is tightly secured, however, I pour the liquid insulating material into the 'F-pieee and branch, and apply heat to the same, so as to expel all moisture, after which the branch is closed by a screw-plug.

. The cap at each end of the line of pipes should have a branch, through which the wires may be conveyed to the instrument or instruments at'the station where they terminate;

and there may be branches at intervals for the same purpose, these branchesbeing filled with resin, pitch, or other solid insulating substance which will prevent the escape of the insulating-liquid. The fibrous wrapping and covering of the wires is thus maintained in a constantly-saturated condition, which insures complete insulation.

During transportation the projecting wires at one end of each pipe G may be protected by a cap, J, and the wires at the other end of said pipes turned up into the branch h of the sential that it should be deprived of allwater, i which may be done by simply heating the liquid until all watery particles have evaporated.

The supply of liquid insulating material may be contained in any suitable reservoir or i reservoirs communicating with one or more of I the branches h, the reservoir or reservolrs being'at such an altitude above the cable that the liquid insulating material therein will be under constant pressure, to secure the best insulation, and to effectually seal the interior of the pipes andprotect the cable from moisture. 1 I claim as my invention- 1 The mode herein described of maintaining a clothed wire or wires contained in pipes in an insulated condition by keeping the fibrous covering of the wires in the pipes constantly saturated with'an insulating-liquid under pressure, as set forth. V

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

\ DAVID BnooKs.

Witnesses:

ALEX. PATTERSON, HARRY SMITH. 

